I.M. Mann, millionaire president of a large corporation, is known as "the man with the iron heart." James Boyd, cashier for Mann's corporation, is delayed one morning because of a dying mother, and is discharged. Then Boyd goes to Union headquarters with his story. The thousands of workmen employed by Mann finally reach the limit of endurance, and at a union meeting, resolve to demand increased wages, a cessation of child labor and other benefits, or strike. He refuses to hear a committee of workmen and says, "I'll close up the factories and let you starve."